RPM began operations on May 31, 1941, a joint venture of Monterrey broadcaster Clemente Serna Martínez, and Azcárraga, who already owned two of Mexico's most popular radio stations: XEW and XEQ.
[1] The business model of RPM was incredibly lucrative; it sold the best XEW and XEQ radio programs to stations throughout interior Mexico, offering these small stations programs they could not produce themselves as well as access to national advertising accounts and the ability to charge more for local advertising.
At one point more than half of all the radio stations in Mexico were affiliated to the company,[2] which also had clients in ten Latin American countries.
[3] The international business continued to flourish into the 1950s; by 1956, RPM had 80 Latin American affiliates and had begun exporting programs to Spain.
The original concession for XHRIO-TV in Matamoros, Tamaulipas was obtained by the Serna family, though they ultimately did not build the station.